(a) State highways are declared to be those primary roads and secondary roads and connecting roads heretofore designated by the State Highway Commission, as shown by a map on file in the office of the commission, entitled “Map of the State of Arkansas Showing State Highway System”, and marked “Revised March 1, 1929”, including those portions of roads extending into or through incorporated towns and cities. The commission is required to preserve the map as a permanent record.
(b) The commission is empowered, with any necessary consent of the proper federal authorities, to make, from time to time, necessary changes and additions to the roads designated as state highways that it may deem proper, and changes or additions shall become effective immediately upon the filing of a new map as a permanent and official record in the office of the commission. However, the commission shall not have authority to eliminate any part of the highway system.